Frank george t usiiingham and henry dubois



(No Model.)

F. G. TUSHINGHAM & H. DUBOIS.

ENGINE STOP.

Patented Oct. 28. 1890.

[KI 61160219 MA /"J W 09W w/m/sg UNITED STATES PATENT OFFICE.

FRANK GEORGE TUSHINGHAM AND HENRY DUBOIS, OF TORONTO, CANADA.

ENGlNE-jSTO P.

SPECIFICATION forming part of Letters Patent No. 439,445, dated October 28, 1890.

Application filed July 2 l 1890. Serial No. 357,533. (llo model.)

T0 at whom it may concern.-

Be it known that we, FRANK GEORGE TUSHINGHAM, builder, and HENRY DUBOIS, clerk, both of the city of Toronto, in the county of York, in the Province of Ontario, Canada, have jointly invented a certain new and Improved Engine-Stop, of which the following is a specification.

This invention relates to that class of engine-stops which are controlled by electricity; and it consists in the peculiar arrangement and combinations of parts hereinafter more particularly described, and then definitely pointed out in the claims.

Figure 1 is an elevation showing our improved engine-stop applied to the valve-gear of an engine. Fig. 2 is an enlarged perspective view of our improved engine-stop. Fig. 3 is a detail showing operation of our device.

Our invention is applicable to all varieties of variable cut-off valve-gears of the Corliss type in which the valves are closed by the independent action of springs.

For the purpose of our invention we have chosen the valve-gear of what is known as the \Vheelock engine.

The spindles A are each connected to one of the inlet steam-valves, and on each spindle A a bell-crank B is fixed. One arm of. each bell-crank B is connected to a spring 0 or other suitable appliance designed to hold the inlet-valve closed when not acted upon by the operating mechanism. The other arm of each bell-crank B is arranged to engage with the arm D, pivoted upon the lever E, which is fixed to the exhaust-valve spindle F, and is connected to the eccentric-rod of the engine. The connection between the bell-crank B and the pivoted arm D is such that the moment the valve-spindle A is rocked the required distance the connection between the arm D and the bell-crank B is instantaneously broken, and the inlet-valve is thereby immediately closed.

As the valve-gear we refer to is well understood, it is not necessary to enter into a minute description of the construction and operation of it, the foregoing being sufficient to enable any mechanic to understand the connection between our improved engine-stop and the class of valve-gear to which it is or may be applied.

Our engine stop is designed to instantaneouslybreak the connection between the bellcrank B and arm D and to hold the two apart, so that the engine will instantly stop for want of steam. I

When the inlet-valves are arranged in proximity to each other, as shown in Fig. 1, we provide two bars G, each bar having a wedge-shaped end a and connected to a disk H, which disk is fixed to the rod I, journaled in a suitably-designed frame J and provided with a spring K, arranged to hold the rod I and its disk H with the bars G in the position indicated in Fig. 1, in which position the wedge-shaped end a of the said bars G hold the arms D out of connection with the bellcrank B, and consequently steam is cut off from the engine so long as the bars G remain in the position indicated.

L is a finger fixed to the rod I, and M is an armature havinga hooked end I), and in order to hold the bars G away from the valve-gear we revolve the rod I so as to draw the bars G in the position indicated in Fig. 2. hen the bars G are in the position indicated, the finger L will be brought below the hooked end Z) of the armature M, and so long as the armature M is held in contact with the magnet N by the action of the closed circuit the bars G will beheld away from the valve-gear.

It is scarcely necessary to state that the magnet N is charged from a suitable battery and that suitable wires are arranged in connection with the magnet N to different parts of the building, so that the electric circuit may be broken from any desired point.

Should any accident occur, the engine may be instantly stopped by pressing on the near est button, and thereby break the circuit, when by the action of the spring 0 the armature M is pulled clear of the finger L, thereby permitting the spring K to revolve the rod I and force the wedge-shaped end a of the bars G between the bell-crank B and arm D, as shown in Fig.1, by which action the bell P is caused to ring by the electric current, which is switched onto the magnet Q in the following manner: A finger R is fixed to the rod I. A spring-plate S is fixed to the post T, which is connected to the electric circuit by the wire U, and is insulated from the frame J. When the rod I revolves, the finger R is brought in contact with'the spring-plate S, and the electric current will then immediately follow along the plate S and rod I to the magnet Q and thence backinto the main circuit, causing the bell P to ring during its passage back through the circuit mentioned.

We do not Wish to confine ourselves to the use of two bars G, nor to the exact-form of the parts shown, as various mechanical changes can easily be made in the mechanism illustrated without altering the invention.

What We claim as our invention is- 1. A bar having a wedge-shaped end and connected at its other end by a crank to a revoluble rod having a finger fixed to and extending from it, a spring being provided in a given position, in combination with a hooked armature arranged to engage with the said finger and operated by an electro-magnet circuit, substantially as and for the purpose specified. V

2. A bar G, having a Wedge-shaped end a and connected by the disk H to the rod I, which is actuated by a spring K, and has a finger L fixed to and extending from it, in combination with an armature M, having a hooked end I) to engage with the finger L, and operated by a magnet, and a spring 0, substantially as and for the purpose specified.

3. A finger R, fixed to the revoluble rod I, which is connected to the electric circuit, in

combination with the spring-plate S, connected to and insulated from the frame J,

substantially as and for the purpose specified.

Toronto, June 14, 1890.

FRANK GEORGE TUSHINGHAM. HENRY DUBOIS.

In presence of- CHARLES C. BALDWIN,

E. CUM INGS. 

